diff --git a/requirements-dev.txt b/requirements-dev.txt
index 6e7338e5..116cdf7e 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -3,7 +3,7 @@
 wheel
 
 # Static analysis tools
-flake8==3.9.0
+flake8==3.9.1
 flake8-annotations-coverage==0.0.5
 flake8-cognitive-complexity==0.1.0
 flake8-comprehensions==3.4.0